Shrimp exports are not expected to recover until next year's second quarter, as Thailand has yet to eliminate early mortality syndrome (EMS) from its shrimp farms.
"Overall shrimp exports remain in bad shape, with the conditions expected to be prolonged until next year," said Poj Aramwattananont, president of the Thai Frozen Foods Association.
"For this year, we expect the country's total production to reach only 200,000 tonnes, with export volume expected to fall by 25% from last year."
EMS first hit a shrimp farm in China in 2009, then moved through Vietnam before spreading to Thailand in mid-2012.
The outbreak has severely damaged the Thai shrimp industry and exports of related products.
Before the disease hit Asian farms, Thailand produced 500,000 to 600,000 tonnes of shrimp annually.
But that figure fell by 42% last year to 270,000 tonnes, while shrimp exports fell by 34% to 187,000 tonnes worth 60 billion baht.
Mr Poj said shrimp export value this year was expected to fall by 12% from last year.
"The Fisheries Department is raising baby shrimp available from imported foreign breeders and has started supplying them to farmers," he said.
"If the hatchery succeeds, we expect Thailand's shrimp farming will improve and exports recover accordingly, possibly in next year's second quarter."
Mr Poj said EMS would remain a threat to shrimp exports.
Other risks include lingering allegations of forced labour and human trafficking made by the US and EU and a possible termination of the Generalised System of Preferences (GSP) in European countries early next year.
If the GSP is cut, Thai processed shrimp will lose EU privileges next Jan 1, and import tariffs will rise to 12-20% from 7%.
In the first eight months of this year, Thailand shipped 89,462 tonnes of frozen shrimp, down 32% year-on-year. Value declined by 17% to US$1.16 billion.
The main market remains the US, which bought 35,000 tonnes, down by 23.9%, with a value of $454 million, down by 5.6%.
Shipments to the EU totalled 11,034 tonnes, down by 39.5%, with a value of $156 million, down 38.5%.
Exports to Japan reached 23,670 tonnes, down 38.2%, with a value of $283 million, down 30.5%.
In other news, the agriculture price index fell by 9.6% year-on-year last month on the back of large supplies of rubber, maize, chicken and eggs.
The September index also fell by 2.7% month-on-month, said Lersak Riewtrakulpaibul, secretary-general of the Office of Agricultural Economics (OAE).
He said prices of natural rubber had been declining steadily against the backdrop of a weak global economy and the slowdown in China, a major buyer of Thai rubber products.
Mr Lersak said the farm price index should continue to drop for another month as more produce enters the market.
The September production index also showed a decline of 3.5% year-on-year and 9.7% month-on-month.
Lower production of paddy rice, pineapple, oil palm and swine contributed to the drop.
In addition, sluggish demand weighed on rubber production last month.
But the OAE expressed confidence that Thailand's agricultural economy would grow within a range of 2.1% to 3.1% as planned this year despite slow growth of 0.8% in the first half.